After online research I am convinced a new replacement battery needs to be registered with the ecu. It seems the system tracks the number of cycles on the battery and charges older batteries more aggressively. New battery will have a shorter life if not reset due to aggressive charging. Now I am looking for an OBD tool to perform this task. I tried the Foxwell NT530 with no luck so far - I have a question into their support. Has anyone had success registering a new battery in the GLC?